A055844 a(n) = (5*n + 9)*binomial(n+8, 8)/9.
1, 14, 95, 440, 1595, 4862, 13013, 31460, 70070, 145860, 286858, 537472, 965770, 1673140, 2806870, 4576264, 7272991, 11296450, 17185025, 25654200, 37642605, 54367170, 77388675, 108689100, 150762300, 206719656, 280412484, 376573120
Offset: 0
References
- A. H. Beiler, Recreations in the Theory of Numbers, Dover, N.Y., 1964, pp. 194-196.
Links
- G. C. Greubel, Table of n, a(n) for n = 0..1000
- Index entries for linear recurrences with constant coefficients, signature (10,-45,120,-210,252,-210,120,-45,10,-1).
Programs
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GAP
List([0..30], n-> (5*n+9)*Binomial(n+8, 8)/9); # G. C. Greubel, Jan 21 2020
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Magma
[(5*n+9)*Binomial(n+8, 8)/9: n in [0..30]]; // G. C. Greubel, Jan 21 2020
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Maple
seq((5*n+9)*binomial(n+8, 8)/9, n=0..30); # G. C. Greubel, Jan 21 2020
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Mathematica
Table[5*Binomial[n+9,9] -4*Binomial[n+8,8], {n,0,30}] (* G. C. Greubel, Jan 21 2020 *)
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PARI
vector(31, n, (5*n+4)*binomial(n+7, 8)/9) \\ G. C. Greubel, Jan 21 2020
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Sage
[(5*n+9)*binomial(n+8, 8)/9 for n in (0..30)] # G. C. Greubel, Jan 21 2020
Formula
a(n) = (5*n+9)*binomial(n+8, 8)/9.
G.f.: (1+4*x)/(1-x)^10.
From G. C. Greubel, Jan 21 2020: (Start)
a(n) = 5*binomial(n+9, 9) - 4*binomial(n+8, 8).
E.g.f.: (362880 +4717440*x +12337920*x^2 +11854080*x^3 +5292000*x^4 +1227744*x^5 +155232*x^6 +10656*x^7 +369*x^8 +5*x^9)*exp(x)/362880. (End)